As a structural design premise, form should always serve function. One explanation of this design premise is that the form of a structure should enhance, and not interfere with, or detract from, the function of the structure in view of its intended purpose and/or use. The same premise should apply, equally, to any smaller component, structure, or element affixed to and/or carried by the structure; as well, to any larger structure to which the structure is affixed and/or which will carry the structure.
While this design premise may be aspirational, it is observably not followed in many structural designs. This is not necessarily the fault of the designer, in that modern design philosophy has tended to be somewhat myopic, focusing on traditional design, manufacturing, fabrication, construction, and assembly techniques.
For example, modern modular constructs, and associated processes therefor, are most often premised upon box-like structures—rectangular structures comprising panel-like members exhibiting perpendicular surfaces. Load-carrying members of such structures typically are joined in perpendicular arrangement. That is, structural, load-carrying, panel-like members are most often joined or attached either at the respective ends of two perpendicularly arranged members, as in an “L”-shaped configuration, or at an end of one member and along a flat surface of an adjacent member perpendicular thereto, as in a “T”-shaped configuration.
In a significant number of applications, such box-like structures, and their resulting modular constructs, may be suboptimal for any of a variety of reasons.
For illustration, one might turn to a particularly exemplary application drawn generally from the cabinetry arts, as specifically applied in the field of private aircraft interior design and construction. In such an application, internal or interior modular structures, such as cabinetry for installation within an aircraft galley, must meet a variety of functional and service requirements, along with Federal Aviation Administration (FAA) regulations, flight-based technical specifications, and design constraints. One might appreciate that, while such modular structures must provide functionality similar to that provided by their conventional, ground-based counterparts, they must do so within an unconventional, difficult environment.
As might be apparent, internal or interior modular cabinet structures for aircraft galleys of the type described often function to support and hold coffee machines and other small appliances, glassware, tableware, flatware, serving pieces, wine bottles, drink containers, and a variety of foodstuffs. They provide countertop and working spaces. They provide drawer and storage spaces. They may be configured with sink, water supply, and drainage systems. They are typically wired for illumination and electrical service. They may have computer or other electronic interfaces. In private aircraft of the sort described, they often are finished with high-end, aesthetically pleasing surfaces.
And yet, while serving the conventional functions described above, aircraft internal or interior modular structures must fit and operate within an extremely tight, carefully allocated space. Not only must they support the above-described contents, as their ground-based counterparts must do, they must, further, safely constrain those contents against the vibrations and stresses arising during ground and flight-based operations. Uniquely, and as typically required by the laws and regulations of one or more countries, they must be designed, manufactured, tested, certified, and installed to meet the rigors of the aircraft industry.
For example, they must be fire resistant. They must be permanently markable, and marked, with identifying indicia sufficient to provide manufacturing traceability in the event of an in-air/in-service accident. They must be capable of withstanding significant gravitation, torsion, vibration, pressurization, and other forces. And they must be capable of withstanding those significant forces throughout long service cycles, often measured in tens of years, without degrading or failing. They must be quiet in the face of vibration, pressure changes, and other in-service stresses and strains to which they are subjected. They must be insulated against those routine, but extreme, temperature fluctuations to which an aircraft is subjected. They must, of course, be lightweight so as to reduce aircraft fuel consumption and, thereby, to increase operational range. For installation and service, they must fit through the relatively small entrance hatch of an aircraft. This represents, of course, only a small sampling of the many considerations attendant such aircraft internal or interior modular structures.
Notwithstanding the extreme environments, requirements, and constraints to which such aircraft internal or interior modular structures are subjected, they continue—disadvantageously—to be designed, manufactured, and assembled as high-tech, box-like structures. The following discussion seeks to convey an understanding of why such a box-like structure is disadvantageous with regard to the exemplary aircraft internal or interior modular structures under consideration.
In order to meet the significant stresses to which they are subjected, while remaining lightweight for the reasons described above, aircraft internal or interior modular structures are constructed using honeycombed-aluminum laminate materials. While these materials are lightweight, they are relatively expensive. Additionally, their principal strength lies along the length of the material. Across the thickness of the material, it is easily pierced, punctured, and crushed. This is, of course, not preferable, since manufacturing, assembly, packaging, transport, and installation processes must be carefully established to ensure that the honeycomb material is not damaged. Additionally, and by their very nature, such honeycombed, laminated materials are of non-uniform density and non-uniform strength; i.e., the center of each honeycomb is less dense and less strong than the surrounding cell wall. Thus, it should be relatively apparent that when trying to form L-joints and T-joints of the type most often used in constructing box-like modular structures, ordinary fasteners, such as screws, bolts-and-nuts, nails, and the like, are of little value.
Rather, and long ago, the aircraft industry adopted the use of panel pins and adhesives to join load carrying panel members. With such construction, a panel pin is embedded between panel members, typically within and between adjacent cells forming the honeycomb material of each panel, and the panel pin is adhered in-place through the use of high-fill adhesives and/or resins. As might be expected, this is an expensive, intensive, by-hand process, requiring custom clamps, fixtures, and/or jigs to hold the panels in fixed and appropriate relative orientation over the extended adhesive drying and cure times required.
Additionally, it will be appreciated that further use of adhesives, resins, and edge-fill products are required to form appropriately finished edges along any honeycombed material that has been cut. This, too, is an expensive, intensive, by-hand process, requiring extended drying and curing times.
Of course, once the aluminum honeycombed materials have been joined into a desired structure, they typically are overlaid, by hand, with appropriate finish materials. This portion of the aircraft internal or interior modular structure construction process typically requires further clamps, fixtures, jigs, tools, and techniques appropriate to the finishing task. Similarly, long drying and cure times are required.
As can easily be seen from this description, design and production cycles are long, requiring highly-skilled and experienced personnel. Repeatability between similar modular structures is often difficult, due to the nature of the by-hand processes. If in-process error or damage occurs, the modular structure often can be repaired only with great difficulty, or sometimes cannot be repaired at all, since joints are adhesively bonded. In any event, extreme care must be taken during any attempted repair or the modular structure may be further damaged.
For the same reasons, should a change order be entered for an existing aircraft internal or interior modular structure, such as may be necessary to upgrade or replace an appliance, or should the owner wish to reconfigure a galley space, for example, to add an appliance, to reconfigure storage spaces, or to modify galley functionality, the existing modular structure most often must be scrapped.
All the while, during this extensive and time-consuming process, an aircraft may lay dormant and out-of-service for weeks or months. When the aircraft internal or interior modular structure is finally ready for installation, it certainly cannot be transported to the aircraft and assembled in-situ; rather, the aircraft typically is flown to an accredited, well-tooled facility—which is most often remote from the aircraft owner's facility—where the aircraft internal or interior modular structure must be installed by specialized, highly-skilled, and experienced personnel.
Thus, as may be seen from the above description, manufacturing of such box-like modular constructs is time consuming and skilled-labor intensive, even when the design of the aircraft internal or interior modular structure is repeated over many units. There are few manufacturing efficiencies to be recognized. The process is heavily dependent upon a variety of clamps, fixtures, and/or jigs. Panel pins, along with adhesives, resins, and edge-fill products of differing types, specifications, and uses are required, with associated long drying and cure times. Configured spaces cannot easily be reconfigured without demolishing and rebuilding the entire structure, or a significant portion thereof. Even when such reconfiguration is possible, it may only be achieved through labor and material-intensive processes.
One might argue that advanced technologies, such as precision computer numerically controlled water jet cutting, plasma cutting, laser cutting, and the like, in combination with advanced, engineered materials of the types discussed above, are capable of producing customized, intricately shaped, flat panels at much higher speeds and throughputs than have been previously possible. While it is true that significant advances have been made in the types and precision of machines for the manufacture, fabrication, and assembly of parts, as well as significant advances in computerized design and manufacturing systems, as well as significant advancements in materials science, such advancements have most often been applied merely to increase the speed with which panels can be produced, and to increase individual-part dimensional accuracy, rather than being exploited to enable a true paradigm shift in the design of the modular structure itself. That is to say, notwithstanding the technological advancements described above, modern structural design philosophy has not heretofore recognized that such advancements may be used to enable the “form should always serve function” design premise; and, thereby, to take advantage of the many accompanying benefits. Rather, it is still most typical that modular constructs are designed and built as box-like forms.
Notwithstanding the above, even when considering human interface factors and ergonomics, box-like modular constructs of the type described are demonstrably suboptimal. Especially within the extremely tight, carefully allocated space of an aircraft galley, a box-like structure is intrusive, in that such structures are inherently bulky and space-monopolizing. Because available space is already tight, human interfaces become even more cumbersome: consider the space necessary to open a drawer or cabinet, and how the person opening that drawer or cabinet must position his or her body within the limited, available space to accommodate that function. Consider, also, how much of the preferred human envelope space—and its reasonably-required, associated functional space—is subordinated to the boundaries of the box-like form.
Furthermore, with box-like forms, adjacent spaces do not flow together naturally; rather, they are interrupted by the aesthetically unpleasing sharp corners and edges of that form. Additionally, such forms are not well-suited to the natural curvature of the human body—many injuries occur when persons attempt to move through tight spaces fitted with sharp-cornered, sharp-edged forms. And this is only exacerbated for high-mounted box-like forms.
In fact, with a box-like construct, the user must adapt to the space and modular configuration provided, rather than the space and modular construct supporting the user's functional and ergonomic needs. If considered honestly, one would conclude that this is not how a user should be required to interact with a workspace—or any other space. That is to say, in such suboptimal, conventional, prior art structures, function must adapt to meet the provided form, rather than the provided form being adapted to meet the necessary or desirable function, as was posited at the outset to be the aspirational design premise.
Although the aircraft internal or interior modular structure described above was chosen to illustrate certain deficiencies in use of the box-like form, there are numerous exemplary modular constructs to which the “form should always serve function” design premise might be extended. Such modular constructs may be seen with reference to any of a variety of modes of transportation, such as aircraft, boats, trains, trucks, equipment trailers, and personal vehicles; and to many of the living, storage, or support spaces attendant such modes of transportation. Such modular constructs may be seen with reference to buildings, wherein forms such as walls, fenestrations, and ancillary structures associated with the buildings may be found. Such modular constructs may be seen with reference to structures internally housed by buildings, wherein forms such as supports, platforms, and storage areas are required. Such modular constructs might also be seen with reference to specialty structures, such as prosthetics for human use, supports for electronic equipment, platforms for solar panels, rack systems, modular work partitions, and the like.
Accordingly, in considering the “form should always serve function” design aspiration set forth at the outset of this discussion, a desirable solution to the above-described deficiencies in the prior art modular constructs and related processes would allow one, in appropriate cases, to avoid the construction of box-like structures. Rather, such a solution would allow a designer to specify a modular construct that better enables a user to gain access to and operate within particularized functional parameters, without hindrance by bulky and space-monopolizing structures.
Such a solution would minimize or eliminate joinder of structural panels in “L” or “T”-shaped configurations. Such a solution would also minimize or eliminate the need to use advanced, expensive, honeycomb materials, while providing for use of materials having appropriate mechanical properties along length and across thickness, at the same time minimizing the required thickness—and, therefore, the weight—of such materials, and, at the end, providing a significantly stronger, yet lighter structure with conventional, relatively lower cost materials.
A desirable solution, further, would reduce or remove the need for use of conventional pins, fasteners, adhesives, bonding agents, edge-fill products, and the like. Of course, without the use of conventional fasteners, such a solution would allow a modular construct to be more rapidly assembled, with a minimal number of required tools, and without custom clamps, fixtures, and/or jigs to hold the panels in fixed and appropriate relative orientation during the assembly process.
A desirable solution would reduce design and production cycles. It would reduce the need for highly-skilled assemblers. It would allow for repeatability between similar modular structures. If in-process error or damage should occur, the modular structure could be easily and inexpensively repaired. Post-delivery or post-hoc reconfiguration and modification could more easily be handled, and with significantly less expense and downtime. Importantly, a desirable solution would allow convenient and relatively inexpensive transportation of unassembled components of a modular construct to a desired location, whereafter the modular structure could be efficiently assembled in-situ or on-site; thereby, minimizing or avoiding extended out-of-service situations.
A desirable solution would, of course, take advantage of the many benefits accompanying advanced manufacturing technologies, such as precision computer numerically controlled water jet cutting, plasma cutting, laser cutting, multi-axis milling and routing, three dimensional (“3D”) printing, injection molding, and the like, while avoiding the need for skilled, by-hand lay-up and assembly processes.
A desirable solution would enhance, not detract from, human interface design and ergonomics. Rather, modular constructs built according to such a desirable solution would better flow into available spaces, reducing footprint and required operating space, while maintaining—or increasing—operational performance, user comfort, and user safety.
And a desirable solution would be useful and functional when applied to any of a variety of applications.
Thus, the “form should always serve function” design premise—and a desirable solution implementing it—would provide a paradigm shift in design, engineering, manufacturing, fabrication, construction, assembly, and/or like processes; in turn, leading to reductions in human labor, reductions in need for the wide variety of fasteners and corresponding assembly tools, reductions in assembly, manufacturing, and related costs, increases in efficiency, increases in design-to-finished-structure speed and predictability, more efficient and improved scalability, more efficient re-purposing and reconfiguring of the structure, decreased weight, increased usable space, and like benefits. In appropriate cases, such paradigm shift in design, manufacture, fabrication, construction, and/or assembly might provide stronger constructs, improved factors of safety, reductions in failure rates, tunable rigidity, flexibility, and/or vibrational dampening within the modular construct, and like benefits, due to improvements in the way load carrying parts are used, combined, aligned, attached, and integrated into and within the structure.
Accordingly, it is to the disclosure of such modular constructs, processes for modular construction, and related systems that the following is directed.